1. Field Of The Invention
The present invention relates generally to footwear, and more particularly to a cushioning, impact absorptive structure useful in fabricating footwear of the type having a shoe upper affixed to a sole and inserts for such footwear.
2. Description Of Prior Art
It has long been known to provide an insole to cushion the impact of a person's foot with a supporting surface. The basic concept of shock absorption by transfer of fluid from the heel to the ball or forward portion of the user's foot has been known as illustrated in the following U.S. Pat. Nos.:
______________________________________ 4,567,677 4,358,902 4,471,538 4,115,934 4,458,430 4,100,686 ______________________________________
These prior art devices are not exhaustive but are exemplary of the state of the art which suggests the presence and/or transfer of fluid which can be employed to achieve shock absorption in a shoe.
While these prior art patents provide improvements in the areas intended, there still exists a great need for a cushioning, impact absorptive structure and which can be easily adapted to be added to existing footwear of different sole sizes and which is relatively simple in construction form which is stable during critical as well as normal phases of walking and running cycles and sustained or lengthy standing by individuals such as police officers, clerks, hairdressers, etc.
Accordingly, a principle desirable object of the present invention is to provide a new and improved cushioning and impact absorptive structure adaptable to form an integral part of footwear and which overcomes the disadvantages of prior art structures.
Another desirable object of the present invention is to provide a structure for fabrication of the insole and which is predetermined and designed for cushioning and absorbing impact forces through the sole of the shoe to the foot of the wearer thereby reducing foot fatigue as well as transmitting a massaging action to the bottom of the foot.
Another desirable object of the present invention is to provide a structure for footwear fabrication of the foregoing characteristics which also conforms itself to the contours of the user's foot when compressed by the user's foot and further the structure of which permits it to be applied to both the left and right footwear by simply inverting one insole device.
Another desirable object of the present invention is to provide a structure for footwear sole construction with a flexible sealed container having two main compartments forming the heel area and the metatarsal area partially filled with a fluid or a combination of fluids and means for metering the transfer of the fluids back and forth from one compartment area to the other.
A still further desirable object of the present invention is to provide a very efficient and effective standing, walking or athletic shoe through application of the structure of the present invention.
A still further desirable object of the present invention is to achieve the above desirable objects with an essentially simple structure, lending itself to inexpensive massproduction.
These and other desirable objects of the invention will in part appear hereinafter and will in part become apparent after consideration of the specification with reference to the accompanying drawings and the claims.